1. Field of the Invention
An apparatus for continuous sulfonization of discrete articles using ultra-dry air, sulfur trioxide gas, and a neutralizing fluid.
2. Description of the Prior Art
The sulfonization apparatuses of the type to which the subject invention pertains continuously treat the surfaces of discrete articles with ultra-dry air, sulfur trioxide gas, and neutralizing fluid. One such apparatus is illustrated in U.S. Pat. No. 6,719,848 to Faykosh et al. wherein the apparatus treats glass sheet substrates with a chemical vapor as they move along a straight conveyor. This apparatus has a chamber bottom with a circular periphery extending about a center axis and defines a chamber bottom opening on the center axis. Another such apparatus is illustrated in U.S. Pat. No. 6,758,910 to Schmoyer wherein dry air and sulfur trioxide gas are mixed to treat discrete articles in a sulfonization apparatus. This apparatus also includes a chamber bottom with a circular periphery extending about a center axis and defines a chamber bottom opening on the center axis for loading and unloading the discrete articles onto a rack inside the sulfonization apparatus for batch treatment of the articles. In addition, the Schmoyer patent shows the feature of employing a neutralizing fluid to the discrete articles after the ultra-dry air and sulfur trioxide gas treatments are employed.
These prior-art sulfonization apparatuses use either straight line conveyors or treatment of discrete articles in separate batches. The straight line conveyor may need to be very long or move at a very slow speed to allow sufficient treatment time for the articles on the conveyor. Using a batch treatment process requires loading and unloading of discrete articles into an apparatus of restricted size and also requires a fixed period of time to treat each batch of discrete articles. Neither method allows an efficient use of both time and space in continuous treatment of discrete articles with sulfur trioxide gas.